1QI9

X-RAY SIRAS STRUCTURE DETERMINATION OF A VANADIUM-DEPENDENT HALOPEROXIDASE FROM ASCOPHYLLUM NODOSUM AT 2.0 A RESOLUTION


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.165 

wwPDB Validation   3D Report Full Report


This is version 3.0 of the entry. See complete history


Literature

X-ray structure determination of a vanadium-dependent haloperoxidase from Ascophyllum nodosum at 2.0 A resolution.

Weyand, M.Hecht, H.Kiess, M.Liaud, M.Vilter, H.Schomburg, D.

(1999) J Mol Biol 293: 595-611

  • DOI: https://doi.org/10.1006/jmbi.1999.3179
  • Primary Citation of Related Structures:  
    1QI9

  • PubMed Abstract: 

    The homo-dimeric structure of a vanadium-dependent haloperoxidase (V-BPO) from the brown alga Ascophyllum nodosum (EC 1.1.11.X) has been solved by single isomorphous replacement anomalous scattering (SIRAS) X-ray crystallography at 2.0 A resolution (PDB accession code 1QI9), using two heavy-atom datasets of a tungstate derivative measured at two different wavelengths. The protein sequence (SwissProt entry code P81701) of V-BPO was established by combining results from protein and DNA sequencing, and electron density interpretation. The enzyme has nearly an all-helical structure, with two four-helix bundles and only three small beta-sheets. The holoenzyme contains trigonal-bipyramidal coordinated vanadium atoms at its two active centres. Structural similarity to the only other structurally characterized vanadium-dependent chloroperoxidase (V-CPO) from Curvularia inaequalis exists in the vicinity of the active site and to a lesser extent in the central four-helix bundle. Despite the low sequence and structural similarity between V-BPO and V-CPO, the vanadium binding centres are highly conserved on the N-terminal side of an alpha-helix and include the proposed catalytic histidine residue (His418(V-BPO)/His404(V-CPO)). The V-BPO structure contains, in addition, a second histidine near the active site (His411(V-BPO)), which can alter the redox potential of the catalytically active VO2-O2 species by protonation/deprotonation reactions. Specific binding sites for the organic substrates, like indoles and monochlordimedone, or for halide ions are not visible in the V-BPO structure. A reaction mechanism for the enzymatic oxidation of halides is discussed, based on the present structural, spectroscopic and biochemical knowledge of vanadium-dependent haloperoxidases, explaining the observed enzymatic differences between both enzymes.


  • Organizational Affiliation

    Department of Molecular Structure Research, GBF (Gesellschaft für Biotechnologische Forschung), Mascheroder Weg 1, Braunschweig, D-38124, Germany. michael-wayand@mpi-dortmund.mpg.de


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Vanadium-dependent bromoperoxidase556Ascophyllum nodosumMutation(s): 0 
EC: 1.11.1.18
UniProt
Find proteins for P81701 (Ascophyllum nodosum)
Explore P81701 
Go to UniProtKB:  P81701
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP81701
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Vanadium-dependent bromoperoxidase556Ascophyllum nodosumMutation(s): 0 
EC: 1.11.1.18
UniProt
Find proteins for P81701 (Ascophyllum nodosum)
Explore P81701 
Go to UniProtKB:  P81701
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP81701
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Modified Residues  3 Unique
IDChains TypeFormula2D DiagramParent
IYR
Query on IYR
A
L-PEPTIDE LINKINGC9 H10 I N O3TYR
PCA
Query on PCA
A
L-PEPTIDE LINKINGC5 H7 N O3GLN
TYI
Query on TYI
A
L-PEPTIDE LINKINGC9 H9 I2 N O3TYR
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.165 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 113.19α = 90
b = 113.19β = 90
c = 272.3γ = 90
Software Package:
Software NamePurpose
X-GENdata scaling
CCP4data reduction
REFMACrefinement
X-GENdata reduction
CCP4data scaling

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2000-06-10
    Type: Initial release
  • Version 1.1: 2008-04-26
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-10-04
    Changes: Refinement description
  • Version 2.0: 2019-12-25
    Changes: Derived calculations, Polymer sequence
  • Version 3.0: 2023-06-07
    Changes: Advisory, Atomic model, Data collection, Database references, Derived calculations, Experimental preparation, Non-polymer description, Other, Polymer sequence, Source and taxonomy, Structure summary